Australians spend 90% of their time indoors [1], whether at home, work, school, in public buildings or in transport. Yet indoor air quality is often overlooked, despite the impact it can have on our health and breathing.
Many people are surprised to learn that indoor air can be 2-5 times, and in some instances up to 100 times, more polluted than outdoor air [2]. Without good ventilation, pollutants can build up and increase the risk of health problems especially for people living with asthma or chronic obstructive pulmonary disease (COPD).
What affects indoor air quality?
Indoor air quality is influenced by a range of factors, including:
- Chemical contaminants, such as volatile organic compounds (VOCs) released from furniture, cleaning products, paints and gas heaters.
- Outdoor pollutants that enter indoor spaces, including cigarette smoke, bushfire smoke, dust storms and vehicle exhaust.
- Biological contaminants, such as mould, bacteria, dust mites, cockroach allergens, and pet dander.
- Particulate matter (PM), from cooking, candles, fireplaces, sanding, or nearby construction.
- Environmental factors, including poor ventilation and high or low humidity, which can intensify the effects of other pollutants.
Why indoor air quality matters for asthma and COPD
Poor indoor air quality affects all Australians. The CSIRO estimates it may cost the Australian economy up to $12 billion each year due to physical and mental ill-health and lost productivity [3].
For people living with respiratory conditions, the impact can be more serious. Even low levels of indoor pollutants can increase airway inflammation and trigger symptoms such as:
- Chest tightness
- Shortness of breath
- Coughing
- Wheezing
Exposure to poor indoor air quality can increase the risk of flare-ups which may develop gradually over hours or days, or occurs suddenly. If symptoms begin – don’t wait – follow the individual’s personal Asthma or COPD Action Plan and commence Asthma First Aid.
Long-term exposure to poor indoor air quality may contribute to reduced lung function, irreversible lung damage, cardiovascular problems, or impact a person’s mental health or cognitive function.
Practical ways to improve indoor air quality
The good news is that small, practical changes can improve indoor air quality and help protect respiratory health.
At home:
- Close doors and windows when outdoor air quality is poor (eg. bushfires or smoke haze events).
- Consider alternatives to wood-burning heaters, such as reverse-cycle air conditioners.
- Use range hoods or exhaust fans when cooking.
- Vacuum floors, mattresses and soft furnishings using a vacuum with a HEPA filter, if possible.
- Shower before bed to reduce pollen transfer onto bedding.
- Clean home air conditioner filters at least every three months.
- Use an air purifier to help reduce allergens and dust.
- Air out new furniture and mattresses in a well-ventilated space.
- When renovating or painting, ensure good ventilation and wear a well-fitted mask.
- Wash bedding weekly in hot water (above 60°C) and consider allergy-friendly mattress and pillow covers.
- Choose low-allergen house plants. Snake plants, for example, are easy to clean, do not produce airborne pollen and can help to absorb toxins.
At work:
- Ask whether lower-fragrance or less irritating cleaning products can be used.
- Support smoke- and vape-free workplace policies. Cancer Council WA has developed a helpful guide with more information here.
- Keep shared spaces clean to reduce mould and pests.
- Wear masks, safety glasses and other recommended personal protective equipment as needed.
- Advocate for a fragrance-free policy at your workplace.
- Ensure ventilation and air conditioning systems are serviced regularly.
- Encourage cleaning of shared equipment such as keyboards and phones.
Notify your employer if you begin to feel unwell or notice triggers in the workplace.
While travelling or in the car:
- Replace car air conditioning filters regularly.
- Air out new seat or steering wheel covers before use.
- Ventilate the vehicle when driving and use recirculated air when outdoor pollution levels are high.
Support is available
Managing indoor air quality is an important part of protecting respiratory health, especially for people living with asthma or COPD.
If you need personalised advice, Respiratory Care WA respiratory educators are here to help. We also offer free asthma education sessions for workplaces, supporting healthier indoor environments for everyone.
Sources:
[1] Department of Climate Change, Energy, the Environment and Water. Indoor air quality. Australian Government, 2021. https://www.dcceew.gov.au/environment/protection/air-quality/indoor-air
[2] American Lung Association. Clean air indoors. 2025. https://www.lung.org/clean-air/indoor-air
[3] Brown, S.K. Beating the $12 billion cost of polluted air. CSIRO Press Release, Ref 98/55, 1998.
